Can we just succumb to the inevitable and work on building a list of the parts of a smartphone that can't be used to spy on you?
I'm thinking 'maybe the battery door'. Any other suggestions?

What's the point of securing any smartphone when all of your activity on the device is captured elsewhere and sold for profit? They don't just count how many times you play your songs. They count how many times you text during the day. They count how many times you click on icons. They count how many seconds you hover over app icons even when you don't buy them in order to market apps catered to your "maybe" whims. Yes, they do this shit. No, it's not called crazy, it's called statistical analysis to the nth degree in order to maximize profits.

The phone is merely the vehicle. What that vehicle can do all depends on the driver. Unfortunately, we've all been thrown in the back of a telco cab and the driver was told to get lost years ago.